Synchronizer activator



United States Patent [72] inventors James l-LLemke Sturtevant; RaymondA. Bazen, South Milwaukee, Wisconsin [21] AppLNo. 807,847 [22] FiledMarch 17,1969 [45] Patented Dec. 1,1970 [73] Assignee J.I.CaseCompany acorporation of Wisconsin [54] SYNCHRONIZER ACTIVATOR 9 Claims, 4 DrawingFigs.

[52] U.S.Cl 192/53, 74/339 [51] Int.Cl Fl6h3/38, F16d 23/04 [50]FieldofSearch 74/339; 192/53 [56] References Cited UNITED STATES PATENTS952,535 3/1910 Loomis 192/53 1,803,535 5/1931 Murray 74/339 2,930,4623/1960 Willis 192/53 3,048,247 8/1962 Cooketal. 192/53 3,063,529 11/1962Cook 192/53 3,078,975 2/1963 Eaton 192/53 32 54 33 .20 1 29 uii fillfiaz110 3,161,270 12/1964 Aschauer 3,374,870 3/1968 Johnston,Jr.

ABSTRACT: A synchronizing mechanism for a transmission including arotatable shaft, a first gearcoaxial with the shaft and free to rotaterelative thereto, and a second gear coaxial with the shaft and fixed torotate therewith. The synchronizing mechanism initially rotates thefirst gear at the rotational speed of the second gear, and subsequentlyestablishes a direct driving connection between the gears. Thesynchronizing mechanism includes a shifting mechanism comprised of anaxially movable coupling member and an actuating member that is movableboth axially and relative to the coupling member. The actuating memberis directly coupled to the second gear, and cooperating cam and camfollower means are provided on the actuating member and coupling member,so that when the actuating member is moved from a rest position to anintermediate position, clutch means associated with the coupling memberand first gear are brought into engagement to rotate the first gear atthe speed of the shaft. Cooperating means are provided on the first gearand the actuating member, so that upon movement of the actuating memberfrom the intermediate position to an engaged position. a direct drivingconnection is established between the actuating member and the firstgear.

Patented Dec. 1, 1970 I 3,543,897

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Patented Dec. 1, 1970 3,543,897

sneet 2 or2 SYNCHRONIZER ACTIVATOR BACKGROUND OF THE INVENTION In thepast, many different structures have been used to bring gears in atransmission up to synchronous speeds before establishing a directdriven connection between the gears. Prior art arrangements have beenstructurally com; lex, and hence are difficult to manufacture, assembleand maintain. Furthermore, known transmission synchronizing mechanismshave not been completely reliable under all conditions of ser- VICe.

SUMMARY OF THE INVENTION The synchronizing mechanism of the presentinvention includes a first clutch means associated with a gear that isfree to rotate relative to a driven shaft. Second clutch means areassociated with a coupling member, and are movable axially of the shaftinto drive transmitting relationship with respect to the first clutchmeans to rotate the first gear at the speed of the shaft. A cam followeris'biased radially outwardly of the coupling member, and an axiallymovable actuating member includes a cam surface that is movable intoengagement with the cam follower means upon movement of the actuatingmember from a rest position to an intermediate position to shift thecoupling member axially and engage the first and second clutch means.The actuating member is directly coupled to a gear fixed to the shaft,so that as the first and second clutch means are brought intoengagement, the rotational speed of the freely mounted gear is graduallysynchronized with the rotational speed of the shaft and the gear fixedthereon. Upon further movement of the actuating member from theintermediate position to an engaged position, the cam follower means iscompressed inwardly of the coupling member, and the actuating membermoves axially relative to the coupling member to establish a directdriven relationship between the rotating shaft and the first gear.

Because the transmission synchronizer of the present invention includesa relatively small number of parts, several of which are conventionalcommercially available items, the synchronizer is relativ:ly inexpensiveto manufacture, assembly and maintain. Furthermore, because of therelative structural simplicity, the transmission synchronizer of thepresent invention is extremely reliable in use. Thus, the major problemsinherent in prior art transmission synchronizers are obviated by thepresent invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary sectional viewthrough a transmission in which the synchronizer mechanism of thepresent invention is used, and illustrates the actuating member in acentral or rest position;

FIG. 2 is a fragmentary sectional view similar to FIG. 1, andillustrates the actuating member in and intermediate or clutch engagingposition;

FIG. 3 is a fragmentary sectional view similar to FIGS. 1 and 2, butillustrating the actuating member in engaged position; and

FIG. 4 is a view taken generally along line 4-4 of FIG. 3, andillustrating the entire synchronizing mechanism in end elevation.

DESCRIPTION OF THE PREFERRED EMBODIMENT While this invention issusceptible of embodiment in many different forms, there is shown in thedrawings and will herein be described in detail one specific embodiment,with the understanding that the present disclosure is to be consideredas an exemplification of the principles ofthe invention and is notintended to limit the invention to the embodiment illustrated. The scopeof the invention will be pointed out in the appended claims.

The synchronizing mechanism of the present invention is illustrated in atransmission that is indicated generally at in the drawings, with thetransmission 10 including a rotatable shaft 11 that is supported insuitable bearings, not shown. Shaft 11 includes a splined portion 12 anda gear 13 is fixed to rotate with shaft 11 by having radially inwardlyextending teeth 14 thereon mesh with the teeth on the splined shaftportion 12. Gears 16 and 17 are provided on opposite sides of gear 13,and gears 16 and 17 are free to rotate relative to shaft 11. Asynchronizing mechanism 18 is provided between gears 16 and 17 forbringing either gear 16 or 17 up to the speed of gear 13 beforeestablishing a direct driven connection therebetween. The elements ofthe synchronizing mechanism for bringing gears 16 and 17 to synchronousspeeds with gear 13 are identical, so that common reference numeralshave been used to indicate corresponding elements for each of gears 16and 17, with the subscript a having been added to the elements of thesynchronizing mechanism for rotating gear 17.

Gear 16 includes an axially extending hub 20 having a plurality ofradially outwardly extending gear teeth 21 thereon. A first clutch means22 is arranged coaxially with shaft 11, and is operatively associatedwith gear 16 for rotation thereby. Clutch means 22 includes a pluralityof annular clutch plates 23 having toothlike inner portions 24 receivedbetween the teeth 21 on gear hub 20. Annularly shaped clutch facingmaterial 25 is provided adjacent the outer ends of disks 23 and on theouter surface ofan annular boss 26 on gear 16.

A second clutch means 28 is arranged coaxially of shaft 11, and ismounted for axial movement into and out ofdrive transmittingrelationship with respect to clutch means 22. Clutch means 28 includes aplurality of annular clutch plates 29 having outwardly facing notches 30drivingly engaged with guide pins 31. As is evident from FIG. 4, threedrive pins 31 are provided in the illustrated embodiment, although twoor more guide pins may be provided, if desired. The notched portions 30of clutch plate 29 embrace reduced diameter end portions 32 of guidepins 31, and the clutch plates 29 are retained on guide pins 31 by asuitable fastener, such as a C-ring 33 that is received in acircumferential groove at the outer end of each pin portion 32. Annularclutch facings 34 are provided on clutch plates 29 in alinement withclutch facings 25, and are movable into drive transmittingengagement'therewith by a shifter mechanism 35.

Shifter mechanism 35 includes an actuating member 37 coaxial with shaft11, and including a splined inner portion 38 that establishes a directdriving relationship with outwardly facing, longitudinally extendingteeth 36 on gear 13; and the cooperative action of teeth 36 and splinedportion 38 mounts actuating member 37 for movement axially relative toshaft 11. Actuating member 37 includes'a central web 39 havingcircumferentially spaced openings 40 therein that slidable embrace theenlarged midportion 41 of guide pins 31.

Actuating member 37 further includes an outwardly extending annularflange 42 adjacent the outer end thereof, with flange 42 includingspaced inner surfaces 43 and 44 that are generally concentric with shaft11, and with an inclined or beveled cam surface 45 connecting surfaces43 and 44. Actuating member 37 is movable between the rest position ofFIG. 1, the intermediate position of FIG. 2, and the engaged position ofFIG. 3 by a suitable shifter member, not shown, that may be defined by ashifter arm having its inner end received within an annular outwardlyfacing groove 46 in actuating member 37. A plurality ofcircumferentially spaced recesses 47 are provided in flange 42 for apurpose to hereafter appear.

Shifter mechanism 35 further includes an annular coupling member 50having a plurality of circumferentially spaced openings 51 that areimpaled by the reduced diameter end portions 32 of guide pins 31.Coupling member 50 includes an outwardly facing circumferentiallyextending recess 52 in the outer periphery thereof, and cam followermeans 53 is mounted within recess 52. Cam follower means 53 includes asplit ring 54 having spaced ends 55 (FIG. 4), and ring 54 is biasedoutwardly of recess 52 by a circumferentially extending wave spring 56that includes a series of circumferentially spaced crests and troughs57.

Retaining means 60 are connected between guide pins 31 and split ring 54for retaining the ring within recess 52, and each retaining means isdefined by a keeper element 61 having a curved portion 62 seated withina circumferentially extending groove in each guide pin portion 32, and areversely bent end portion 63 overlying ring 54. Keeper elements 61 notonly function to retain guide ring 54 within recess 52, but also serveto retain the coupling member 50 against the shoulder 64 on guide pin 31at the junction between the guide pin portions 32 and 41. The recesses47-i n the flange 42 of the actuating member 37 allow the actuatingmember 37 to be shifted from the rest position of FIG, 1 to the engagedposition of FIG. 3 without interfering with the bent end portions 63 ofthe deeper elements 61.

Assuming that the shaft 11 and gear 13 are rotated at a predeterminedspeed, and it is desired to rotate gear 16 at that speed, actuatingmember 37 is initially shifted to the left from the rest position ofFIG. 1 to the intermediate position of FIG. 2 to move the cam surface 45into engagement with the split ring 54. As the actuatingmernber 37 movesinto the intermediate position, the cam and cam follower means cooperatetoshift the coupling member 50 axially relative to shaft 11, and tobring the clutch means 28 into engagement with the clutch means 22 tothereby gradually increase the rotational speed of gear 16 to that ofshaft 11 and gear 13. When gear 16 is rotating at the speed of shaft 11and gear 13, actuating member 37 is moved from the intermediate positionof H6. 2 to the engaged position of FIG 3, and during this movement, camsurface 45 compresses the split ring 54 radially inwardly against thebias of wave spring 55, and actuating member 37 moves-axially relativeto coupling member 50 to place the spline teeth 38 on actuating member37 in direct driving engagement with the gear teeth 21 on gear 16.

From the above, it will be apparent that if shaft lland gear 13 arerotating at a predetermined speed, and it is desired to rotate gear 17at that speed, actuating member 37 is moved to the right instead of tothe left, as described above. Furthermore, if gear 16 or gear 17 isrotated at a predetermined speed by gears 66 or 67, respectively, shaft11 may be brought up to a synchronous speed by actuating thesynchronizing mechanism 18 in the manner described above.

Weclairn:

1. in a transmission including a rotatable shaft, a first gear coaxialwith said shaft and free to rotate relative thereto, and a second gearcoaxial with-said shaft and fixed to rotate therewith, a synchronizingmechanism for first rotating said first gear at the rotational speed ofsaid second gear and for then establishing a direct driving connectionbetween said gears, said mechanism comprising: first clutch meanscoaxial with said shaft and operatively connected with said first gear;second clutch means coaxial with said shaft and mounted for movementaxially of said shaft into and out of drive trans mitting relationshipwith said first clutch means; a shifter mechanism for moving said secondclutch means, said shifter mechanism including a coupling member coaxial.with said shaft and mounted for movement axially thereof, said couplingmember having said second clutch means operatively connected therewith,anactuating member coaxialwith said shaft, said actuating member beingmounted for movement axially of said shaft and relative to said couplingmember from a rest position to an engaged position, means establishing adirect driving relationship between said actuating member and saidsecond gear in both the rest and engaged positions of the actuatingmember, cooperating means on said actuating member and said couplingmember for first connecting said members for movement together relativeto said shaft during initial movement of said actuating member from saidrest position to an intermediate position between said rest position andsaid engaged position and for then allowing said actuating member tomove relative to said coupling member and relative to said shaft duringmovement of said actuating member from said intermediate position tosaid engaged position, said cooperating means including a radiallyinwardly facing cam means on said actuating memberand a radiallyoutwardly facmg cam follower means on said coupling member, spring meansbiasing said cam follower means outwardly of said coupling means intoposition to be engaged by said cam means, whereby when said actuatingmember moves from said rest position to said intermediate position, saidcam means engages said cam follower means to shift said coupling memberand move said second clutch means into engagement with said first clutchmeans so that said gears are rotated at the same speed; and cooperatingmeans on said first gear and said actuating member for establishing adirect driving connection therebetween when said actuating member movesfrom said intermediate position to said engaged position.

2. The invention set forth in claim I in which said coupling member isan annular disk having a recess in the outer periphery thereof, saidrecess having said spring means and said cam follower means therein.

3. The invention set forth in claim 2 in which said spring means isdefined by a generally annularly shaped spring member having alternatingcrests and troughs, and wherein said cam follower means is defined by agenerally annularly shaped split ring embracing said spring member.

4. The invention set forth in claim 3 in which said actuating memberincludes a circumaxially extending flange having a beveled surfacedefining said cam means.

5. The invention set forth in claim 4 in which a plurality of guide pinsextend outwardly from said coupling member in mutually parallelrelationship with respect to said shaft, and wherein said actuatingmember has a plurality of openings therein, each opening slidablyreceiving a guide pin.

6. The invention set forth in claim 5 in which retaining means areconnected between each guide pin and said split ring for keeping thesplit ring in said recess.

7. The invention set forth in claim 6 in which said coupling memberincludes a plurality of openings alined with the openings in saidactuating member, said guide pins extending through said alinedopenings, each of said retaining means being arranged to hold saidcoupling member at an axially fixed position on said guide pins.

8. The invention set forth in claim 7 in which each guide pin has an endportion of reduces diameter defining an outwardly facing shoulderagainst which said coupling member abuts, said guide pins each furtherhaving a circumferentiully extending recess outwardly of said couplingmember, and wherein each retaining means is defined by a keeper memberhaving a curved portion seated in a guide pin recess and a reverselybent end portion overlying said split ring.

9. The invention set forth in claim 8 in which the circumaxiallyextending flange of said actuating member includes a pluralityofcircumferentially spaced recesses, each alined with the reversely bentend portion of one of said keeper members, whereby said actuating membercan move from said intermediate position to said engaged positionwithout interfering with said keeper members.

